Download Crop Module: Garlic - Red Tractor Assurance

Crop Module: Garlic
Effective 1st September 2015
Welcome
T
his crop specific module for garlic has been written
to complement and avoid duplicating the generic
principles of the Red Tractor Farm Assurance Fresh
Produce Scheme standards. It is advisable to read the
Red Tractor Farm Assurance Fresh Produce standards
before reading this crop specific module. This module is
designed to stimulate thought in the mind of the reader.
It contains crop specific guidance and standards, where
applicable, in addition to the requirements stated in the
generic Fresh Produce standards.
Within this module the important requirements outlined
in the crop specific standards section will be verified
during the Red Tractor Farm Assurance assessment and
compliance will form a part of the certification/approval
decision.
Disclaimer and trade mark acknowledgement
Although every effort has been made to ensure
accuracy, Assured Food Standards does not accept any
responsibility for errors and omissions. Trade names
are only used in this module where use of that specific
product is essential. All such products are annotated®
and all trademark rights are hereby acknowledged.
Notes: Pesticide Information
General Introduction
Following a systematic approach will help growers identify
and manage the risks involved in crop production. This
module is based on a typical crop production process and
food safety, health & safety, environmental and quality
hazards are identified. Appropriate controls may then
be established to minimise risk. Food safety and health
& safety issues always take precedent over quality and
environmental controls. The layout of this module follows
the same structure as that used in the Red Tractor Farm
Assurance Fresh Produce Standards. The content of the
module is reviewed prior to the issue of updated editions.
The review process considers both new developments
and all relevant technology which has emerged since the
last review was completed and which have been found
to be both workable by the grower and beneficial to the
environment. The aim is to transfer such information and
technologies to growers.
Acknowledgements
Red Tractor Farm Assurance Fresh Produce gratefully
acknowledges the contribution of all consultees in the
preparation of this protocol, in particular Glen Allingham,
Really Garlicky Company.
The Red Tractor Fresh Produce team has been working
with Fera to provide tailored access to the LIAISON
database for all Red Tractor Fresh Produce members.
This system allows individual growers access to all
information for plant protection products approved for
use under the Red Tractor Fresh Produce Scheme.
LIAISON can be accessed under the Produce tab via the
“Checkers and Services” page where you will also find
a user manual. Searches will be filtered specifically for
the crops for which you are registered. Once you have
logged onto the site and clicked on the LIAISON hyperlink
you will be directed to the LIAISON home screen.
You will need a username and password and these will
be sent once you have registered:
http://assurance.redtractor.org.uk/rtassurance/
services/Registration/members.eb .
Front cover image credit: Glen Allingham Really Garlicky Company.
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Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
Content
Contents
ADDITIONAL REQUIREMENTS AGAINST CURRENT STANDARDS 02
CROP SPECIFIC STANDARDS02
CHOICE OF VARIETY, ROOTSTOCK AND PLANT HEALTH CERTIFICATION03
SITE AND SOIL MANAGEMENT 03
ENVIRONMENTAL PROTECTION AND CONTAMINATION CONTROL03
PEST, DISEASE AND WEED CONTROL 04
NUTRITION 07
IRRIGATION07
HARVEST AND STORAGE07
RESIDUES AND CONTAMINANTS09
APPENDIX 1: TYPICAL APPLICATION RATES FOR NUTRIENTS 10
APPENDIX 2: GUIDELINES ON MINIMISING PESTICIDE RESIDUES 11
ADDITIONAL REQUIREMENTS AGAINST CURRENT STANDARDS
None for this crop module
CROP SPECIFIC STANDARDS
None for this crop module
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
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GUIDANCE
CHOICE OF VARIETY OR
ROOTSTOCK AND PLANT HEALTH
CERTIFICATION
Varietal yield, quality and storage characteristics should
be utilised to optimise the performance of garlic crops.
The need for specific seed applied pesticides should be
justified and documented.
As there are no multipliers of garlic at present growers
need to keep a nursery stock for future plantings which
should be monitored and any diseased or rogue plants
should be removed.
SITE AND SOIL MANAGEMENT
SITE HISTORY
Soil type and latitude have a major influence on the
production system that can be used and on the quality
of resulting bulbs.
The most suitable soil types are sandy loam to sandy
clay loam, very fine sandy loam (silts), and some peat
based soils.
The crop produces a coarse rooting system and whilst
requiring a degree of firmness for good root/soil contact,
the soil should be free from compaction and well drained.
Irrigation is an essential requirement for production on
sand-based soils (excluding silts).
Rotation and crop siting
Rotation has a role in minimising disease problems but
may not prevent the build-up of two major soil-borne
diseases over the course of time. It is generally accepted
that the minimum rotation should be 1 in 4 years and
ideally up to 6 years.
Garlic crops should be separated by a minimum distance
of 800m from any commercial onion crop. Isolation
reduces the spread of wind-dispersed leaf diseases.
However, this may only be possible to a limited extent in
commercial practice.
Choice of production system
Garlic can be produced in a number of different ways:
i. Over-wintered, cloves planted in late September/
October for harvest the following June/July.
iii. Spring drilled from bulbils for harvest late August/
September. This will produce a single round clove
which if planted the following year will develop into a
conventional bulb
The choice of cultivar within each section has only a
minor influence on disease susceptibility. Leaf diseases
are encouraged by increasing population density and
by humid conditions. Over-wintering types are the most
susceptible to leaf diseases with spring-drilled being the
least susceptible. Soil type as well as requirements for
continuity of production will influence choice of production
system. Larger bulb size, from lower plant populations
has assisted reduction of foliar disease incidence.
Latitude
Bulbing is influenced by day length and hence site
selection is influenced by latitude. In general terms,
spring planting is only recommended in England
ENVIRONMENTAL PROTECTION &
CONTAMINATION CONTROL
Integrated crop management
Garlic is subject to a number of disease problems
and it is a guiding principle that pesticide inputs
should be minimised through prevention rather
than cure.
An integrated approach should be adopted using the
following steps:
Good management and planning
a. Careful site selection to avoid potential or previous
problems
b. Sensible crop rotation to avoid build-up of soil-borne
problems or disease carry over from one crop to
the next
Cultural preventative techniques
a. Good crop and field hygiene to minimise spread
of soil borne problems by cultivation equipment
etc. This is particularly important with green garlic
harvesting. There is therefore a greater risk of
transporting disease more widely with machinery
b. Avoiding spread of garlic waste except on farms
unlikely to be involved in garlic production
ii. Spring planted cloves for harvest in July/August.
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Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
c. Minimise wind blown debris from harvesting and
grading operations. Crop residues should be
ploughed in as soon as possible. Waste trailers
should be sheeted at all times in transit
Corrective action
Where control of pests/diseases is still required the
following approach should be adopted:
a. Establish the need to take corrective action by regular
monitoring and reference to forecasting techniques,
when available
b. Consider effect of prevailing weather conditions
This pest also affects sugar beet and will survive on
certain host weeds. Affected fields will remain so for many
years even in the absence of garlic crops. Avoidance of
such fields is, therefore, the first consideration.
Stem and bulb eelworm can cause serious losses in
both field and store. Early field infection will cause foliage
distortion followed by death of seedlings and resultant bare
patches in fields (only in very serious cases will an entire
field be uniformly infected). The margin of such patches
invariably contains less infected bulbs with characteristically
distorted foliage and soft bulbs when mature. Infected bulbs
deteriorate rapidly in the initial drying process; the effects
are exacerbated by stage 1 temperatures (25-30°C).
c. Where action is required, as a principle, the possibility
of using biological or natural methods should be
considered first
Stem and bulb eelworm can be spread to previously
uninfected fields by contaminated bean seed and care
should be taken to use only certified seed if beans are
grown on the farm.
d. If chemical control is needed the following
points should be considered, subject to achieving
effective control:
Good drainage is also essential as localised wet areas
will encourage eelworm build up.
n
use
the least toxic and persistent product.
n
use
the most selective product to reduce the impact on
naturally occurring beneficial organisms.
n
use
the minimum effective dose rate.
n
use
appropriate application methods with properly
maintained equipment.
Thrips (Thrips tabaci)
Thrips are a pest of variable incidence. Control measures
should be based on regular monitoring when the weather
conditions are appropriate for attack. More commonly
known as ‘thunder bugs’; thrips are most likely to attack
garlic from June to August. The need for treatment should
be judged on appearance of the orange nymphs as well
as the symptoms on the plant.
n
use
This pest multiplies in the growing centre of the plant and
leaves appear with silvery flecking and leads to distortion
in more serious cases.
Growers should ensure that the minimum number of
chemical applications are made to achieve good control
for example in controlling downy mildew.
A certain level of flecking is acceptable before treatment
is necessary, noting that control approaching harvest is
of importance. Adult thrips can feed for a considerable
period under skins of bulbs during storage causing
downgrading in quality.
the minimum number of chemical applications to
achieve good control, for example in controlling downy
mildew and Botrytis.
N.B. exceeding the maximum individual and maximum
total dose rate is illegal under COPR.
PEST, DISEASE AND WEED
CONTROL
PEST CONTROL
Stem and bulb eelworm (Ditylenchus dipsaci)
Eelworm attack is initiated by wet conditions. Control
measures are influenced by soil type and local
considerations.
Routine control measures are most likely to be necessary
on very fine sandy loams and on heavier sandy clay
loams, again based on previous knowledge of the
area/field.
When treatment is considered necessary use
deltamethrin. A repeat application may be necessary
depending on prevailing weather conditions.
DISEASE CONTROL
White rot (Sclerotium cepivorum)
A persistent soil-borne disease that infects soils for many
years, this disease is the most serious threat to garlic
growing in many parts of the world where the climate
is suitable.
Its long persistence (in order of 100+ years) is reflected in
local knowledge and many fields are of known infection
status. Incidence is not confined to garlic growing areas
and source often relates to cottage gardens where onion
or garlic waste has been composted in the past.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
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The disease initially infects roots and spreads back into
the bulb causing destruction of tissue from the base
upwards. This destruction is accompanied by a white
cotton wool-like fungal growth. Early infection causes
bulbs to completely rot in the field and later infections
cause the total collapse of bulbs in store. Progress of
infection is checked at the initial drying stage (28-30°C)
but continues when the store is cooled.
There is development of control measures but it is
therefore essential to:
Note infection areas on farm maps and not only avoid
such areas but also where possible avoid spreading
contaminated soil to other parts of the farm, particularly
with cultivation equipment.
Monitor crops to ensure that any occurrence of infection
is recorded. Premature yellowing of foliage in patches is
the most usual indicator.
Make every attempt to avoid harvest of infected bulbs.
Field population of resting spores (sclerotia) can be
reduced by hand collection of infected bulbs but this
is recommended only for small areas where such action
is practical.
EAMU for use of Folicur (tebuconazole) and Signum
(boscalid + pyraclostrobin). Both Folicur and Signum if
applied early will give some control of field infections.
Fusarium base rot (Fusarium culmorum f.sp. cepae)
Basal rot of garlic is caused by Fusarium culmorum.
Soilborne inoculum infects garlic through the stem plate
rather than through roots or storage leaves. Leaves of
infected plants may not produce disease symptoms, but
can be a source of the disease. Transmission can occur
when infested soil or debris is transported on equipment,
seed, or runoff water. The fungus can survive indefinitely
in the soil. Fusarium culmorum can also infect elephant
garlic, but not to the same degree as garlic. Onion is not a
host. Symptoms include pre-emergence decay of cloves
and seedlings. Stem plates and storage leaves may
decay in the field during the growing season. Lesions
may have a reddish fringe. Disease expression is erratic
from year to year and field to field. Post-harvest decay
may involve a single clove or the entire bulb.
Cultural Control: Growers commonly rotate garlic with
non-host plants to reduce disease pressure. Cereals are
a host of garlic strains of Fusarium culmorum. Growers
also avoid planting in fields with a history of basal rot
problems. The primary cultural control of basal rot is
curing bulbs properly before storage and storing the
garlic at cool temperatures, as F. culmorum is favoured
by warm conditions. Fields with good drainage and
freedom from sub-surface pans (or compaction) will
minimise problems. There are no chemical treatments.
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Downy mildew (Peronospora destructor)
Downy mildew is a serious foliar disease that commonly
requires routine treatment. The disease is readily spread
by air-borne spores and encouraged by warm humid
conditions, closely following the infection criteria of
potato blight.
Maintaining 500m separation between overwinter
(most susceptible) and spring crops will minimise
cross-infection.
Infected crop debris should be ploughed in as soon as
possible after harvest to minimise any carryover.
Use of weather based prediction models is anticipated in
the near future.
Treatment should be based on routine monitoring so that
infection can be identified at an early stage. Following
this, a routine spray programme is necessary to ensure
adequate control using currently approved fungicides. It
is recommended to alternate chemical groups to avoid
the risk of resistant strains developing.
Leaf Blight (Botrytis squamosa)
Leaf spot is a disease that affects the foliage in cool wet
conditions. It most seriously affects either seedlings of
overwintered varieties in the autumn or the foliage of
spring-planted varieties, particularly closer to harvest.
This disease will require treatment in occasional seasons
only. The risk of infection increases with increasing
crop density.
Development work is in progress to predict infection
conditions (as with downy mildew).
Treatment is usually combined with downy mildew control
in overall fungicide programmes and should be based on
routine monitoring. Disease incidence is more tolerable
than downy mildew since the disease is less progressive
and less likely to cause serious crop loss.
Garlic foliage becomes more susceptible to infection
as harvest approaches and as the density of the crop
canopy increases. Early infection of the outer leaves can
affect skin retention in store.
Leaf blotch (Cladosporium allii-cepae)
Leaf blotch is a disease that occurs when the combination
of temperature and long periods of leaf wetness allows
germination and penetration of the fungus. In such years
infection can result in complete defoliation. Symptoms
are bleached elliptical eyespots on the leaves that spread
parallel to the leaf veins and can destroy entire leaves.
Routine control measures for this disease are not
normally necessary.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
Treatment should be based on routine monitoring so
that infection can be identified at an early stage. Once
identified use of propiconazole should give control.
Neck rot (Botrytis allii, porri, aclada)
The fungus organisms that cause neck rot, including
Botrytis porri and B. aclada, survive the winter as
sclerotia on dead plant parts in the soil and on infected
bulbs. Infection occurs through neck tissue or through
wounds. In garlic, neck rot is generally a more serious
problem than is leaf blight. Symptoms may first appear
on the neck of the plant near the soil line in the spring.
The fungus moves rapidly into the neck region of the
bulbs causing a water-soaked appearance. A gray
mold develops on the surface, later producing black
sclerotia. Before bulbing, plants may die or recover
depending on weather conditions. Bulbs infected late in
the season break down and are often infected by other
disease organisms.
Cultural Control: Growers avoid excessive nitrogen and
irrigation, especially late in the season. They practice
good weed control to aid air movement through field and
to keep relative humidity low. When harvesting, growers
allow tops to mature, then lift or undercut plants to avoid
bruising and mechanical injury. Finally, they make sure
that the garlic is properly cured before storing.
Avoiding spread from the previous season’s crops is
important. Where refrigerated stores are being emptied
late in the season, when the new season’s crop is
established (April - June), every effort should be made
to minimise wind blow of debris. The new season crop
should be planted as far away from cold stores as
practical, ideally a minimum of 800m. If appreciable
levels of neck rot are identified in store, these lots
should be marketed before emergence of the new
season’s crop.
Chemical Control: Fungicides are not generally used by
growers against neck rot, as cultural methods control the
disease at this time.
Blue mould (Penicillium spp)
Penicillium spp. cause blue moulds to develop on bulbs
in store, between the skin and scale tissue. These
blue moulds are mostly of a secondary nature but can
be associated with a physiological disorder known
commonly as watery skin. In such cases scale tissue
and inner skins become brown and ‘watery’. This favours
Penicillium which then sporulates freely.
Penicillium is common on stored bulbs but mostly at low
levels that do not cause marketing or storage problems.
Potential problems can be minimised by adherence to
storage procedures. High humidities in store, irrespective
of temperature, will increase incidence and level of
Penicillium infections.
OTHER BACTERIAL PATHOGENS
A number of bacteria species will cause either foliar
dieback in the field or deterioration during storage.
Field and store symptoms can be linked but the
absence of visual effects in the field may still result in
storage problems.
Bacterial diseases are initiated in the field and spread
principally by water splash. Wet seasons, are therefore
more likely to result in storage losses.
The main pathogens are detailed as follows:
Pseudomonas allicola
This disease can cause serious problems in store since
the bulb’s scale tissue ‘soft’ rots completely but the outer
skins retain the rotten tissue. Once the crop is moved, the
bulbs split and cause loss of quality by down grading of
adjacent bulbs. Up to 40% infection has been recorded.
The disease is temperature sensitive and where
problems are anticipated, can be minimised by reduced
drying temperatures.
Recent work at HRI has resulted in a prediction system
based on serological agglutination techniques. It is
therefore possible to test bulbs at harvest. This technique
is now available as a specific test kit.
Erwinia spp
Erwinia infects over a wide temperature range and tends
to affect single scales within a bulb. When cut these bulbs
reveal one scale of firm tissue that has turned brown.
Infection of bulbs is linked to the dieback of single leaves
in the mature plant. Infection then spreads back to the
scale at the base of the affected leaf. Incidence of this
disease varies according to season, and levels rarely
exceed 2-3%. Infection is normally more prevalent in late
harvest drilled crops.
Lactobaccillus spp
These bacteria cause water soaking and an odour
characteristic of vinegar. This bulb disease is very
temperature sensitive and becomes increasingly active
above 30°C. It has not been a problem since adopting the
now accepted drying and storage procedures detailed in
Section HS.
SECONDARY BACTERIA
A range of secondary bacteria can follow on damaged
or previously infected tissue. In wet seasons root death
is often followed by soft rotting bacterial infection. It is
not unusual in most seasons to find occasional plants
which have died with soft rot symptoms but these are not
normally associated with storage disorders.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
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APPROVED USES NOT INCLUDED ON THE
PRODUCT LABEL
NUTRITION
In many circumstances, particularly for minor crops,
product labels do not include all of the approved uses
and growers wishing to check the approval notice of
a particular product should note that this information
is available using the LIAISON® search accessible via
their RED TRACTOR Farm Assurance home page after
logging in.
Garlic requires a fertile soil with adequate reserves of
the major nutrients nitrogen, phosphate, potash and
magnesium. Application of fertiliser (see Appendix)
should be on the basis of regular soil analysis, ideally
preceding each crop. Soil pH is important and should
be in the range 6.5 - 7.0. Garlic is most responsive
to phosphate and less responsive to nitrogen than
leafy vegetables.
A search on the ‘Extensions of Authorisation for Minor
Use’ page of LIAISON® by crop or product name should
yield a results page. A click on the product name should
link to a summary of the approval information. Near the
bottom of the summary is the specific off-label number
(e.g. 0246/09) and this link will open up a pdf of the
current EAMU document giving details of the extension
of use.
Nitrogen application should be minimised where
possible and ideally based on residual nitrogen sampling
in conjunction with the ‘Well-N’ predicition model,
developed by HRL. This will ensure adequate nitrogen
without excess that could lead to leaching into ground
water. Late application from bulbing onwards should
be avoided.
Deficiency Risk
Soil Type
Magnesium
Manganese
Copper
Zinc
Iron
Boron
Sand
High
High
High
Moderate
Moderate
Low
Sandy Loam
High
High
Moderate
Moderate
Moderate
Moderate
Silt
Moderate
High
Moderate
Low
Low
Low
Peat
High
High
Moderate
Low
Low
Moderate
IRRIGATION
Adequate soil moisture is usually present for crop
establishment of autumn/spring-drilled cloves.
There is a marked growth response to irrigation on all
light soils during dry periods. It leads to an increase
in leaf number and size, which maximises bulb size
and yield.
Scape removal and storage
Late irrigation can produce softer bulbs, increases
bacterial incidence and causes bulb staining and should
be avoided. Where available, an irrigation scheduling
system should be used to ensure efficient use of
water resources.
Some varieties of hardneck garlic will bolt, the flowering
shoot (scape) will normally need to be removed in order
to allow the bulb to achieve its full potential weight. This
operation is normally done by hand.
HARVEST AND STORAGE
Scapes are edible and if sold for human consumption
all harvest intervals must relate to the harvesting of
the scapes.
Maleic hydrazide (MH)
It is accepted, and clarified by HDC-funded trials, that
as an aid to the maintenance of quality, it is necessary
to apply maleic hydrazide pre-harvest as a growth
suppressant at 10% leaf fallover. All sprout suppressant
treatments should be justified.
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The area treated should be related to the projected
marketing dates of the bulbs. Application of MH is
not necessary on crops to be marketed prior to the
1st December, in so far as can be judged in advance.
Crops should be sprayed according to manufacturer’s
recommendations, lower rates normally prove adequate
for crops in ambient storage.
Storage of the scapes should be at 5-7ºC in cleaned
trays or boxes.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
Harvest
Topping of the crop is essential to ensure ease of handling
into store and minimising restriction to airflow during the
initial and most critical drying phase.
It is a case of individual judgement as to the best harvesting
system, depending on soil type, local circumstances and
prevailing weather conditions.
Top lifting harvesters are recommended to minimise
damage and soil contamination.
All trailers or boxes must be cleaned before they are used
to transport loose garlic from the field and the cleaning
must be recorded.
The maximum loading height accepted in practice is
up to 4m. The maximum quantity that can be loaded at
any one time will depend on the airflow specification of
the store.
Stores must be cleaned before garlic is stored in bulk
and this cleaning must be recorded.
When washing Green garlic only, the water used
for washing the harvested crop should be used with
conservation as a priority.
Storage
It is an essential prerequisite of garlic production
that adequate store loading and storage facilities are
available. The use of expert management, correct airflow
and temperature in properly designed and constructed
stores cannot be overemphasised in minimising storage
disorders and maximising quality.
Controlled storage facilities should be capable of
achieving temperature and humidity targets set out in the
following sections.
Drying (stage 1)
Initial drying (stage 1) to be achieved by a minimum
25°C and a maximum of 32°C. 28°C will be the norm
but special circumstances may require a slightly
lower temperature (e.g. the incidence of bacterial diseases).
In practice, initial drying requires a minimum airflow of
425m3/hr tonne with suitable fans and ducting system.
Crop drying can be undertaken in boxes but such
systems are generally less efficient due to air leakage
and greater difficulty in obtaining uniform airflow. The
store design should allow recirculation of air to minimise
fuel usage and to maintain humidity. Specification of the
humidity regime during initial drying will vary according
to condition of crop. A target duct range 50-65% relative
humidity (RH) is normally accepted.
An important point in minimising storage problems
and achieving quality is that these specifications are
combined with a maximum Stage I drying time of 7 days
from initial loading of the store. The specifications become
more important with later harvests. Some relaxation is
acceptable, however, for early crops harvested in ideal
conditions and not scheduled for long term storage.
Curing (stage 2)
After initial drying to a ‘rustle dry’ condition, it is necessary
to maintain temperature and control humidity to cure
skins and complete the drying in the air spaces between
cloves (stage 2).
Stage 2 is accomplished using intermittent ventilation
at 25°C with humidity control by sensors amongst
the garlic. It is necessary to ventilate when humidity
exceeds 75% RH at the top of the stack and continue
until humidity is reduced to 65% RH. Airflow specification
is 170m3 /hr tonne. Curing normally takes 1-2 weeks.
Once all moisture has been removed from the bulb
neck and between the cloves, it is possible to begin
temperature reduction.
Cooling (stage 3)
Cooling is accomplished gradually, ensuring that
the stored crop does not fall below average ambient
temperature (unless refrigeration facilities are available).
Automatic control is advised, using a differential setting
such that ventilation is initiated when outside temperature
is 3°C or more below crop temperature. An override
prevents overcooling and more sophisticated stores
incorporate automatic vents to mix internal/external air.
These also control the duct temperature for cooling and
humidity in the earlier stages.
Stores should be insulated such that, when outside
conditions are unfavourable, it is possible to close up
with the minimum heat loss. Minimum temperature in
ambient stores should be 5-8°C dependent on location
and average ambient conditions.
Refrigerated storage is ideal since crop temperature
is independent of outside conditions. It is possible
to cool crops more rapidly after completion of curing
and normally switch over to refrigeration at 10-12°C
crop temperature.
Refrigeration at -2.5 to -3.5°C is essential for bulbs
scheduled to be marketed from February to end of May/
Early June. Controlled Atmosphere is necessary for
storage beyond this period. Actual change over date will
vary accordingly to season.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
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Storage disorders
RESIDUES AND CONTAMINANTS
Where attributable to a specific pest or disease, storage
disorders are reviewed in the appropriate sections of
Pest, Disease and Weed Control. This section covers
those factors where specific diseases or pests are
not implicated.
Red Tractor Farm Assurance Fresh Produce is aware
that a key area in the production of fresh produce which
requires continued attention by growers and their advisers
is that of keeping pesticide residues to a minimum. This
issue is not just one of meeting the MRL trading standard
but ensuring that any individual or multi residues are kept
as low as possible below this level.
Compression damage
This results in deformation of bulbs and hence a more
irregular shape.
It is a factor of season, bulb maturity, and sometimes
variety rather than height of storage. Compression can
occur in box storage as well as bulk storage although
generally less so. In either case, affected bulbs can be
found from 30cm and below.
Compression damage will be worse if the bulbs are
harvested very early and in association with wetter
seasons and late maturity. Some bulb deformation
can result in the field where bulbs are growing in
close proximity to each other. Compression damage is
self-correcting to a degree when the pressure is released,
whether caused in field or store.
The key targets are:
n
Optimising late applications of fungicides
insecticides to the edible part of the crop
n Optimising
n Ensuring
and
the use of post-harvest treatments
minimum harvest intervals are followed
n
Ensuring
that application equipment is applying
products correctly
See Appendix for pesticide targets and guidelines on
this crop.
Skin retention
A number of factors affect skin retention and it is
essential that ‘lots’ or batches are handled at the correct
temperature and humidity relative to ambient conditions.
No firm specification can be given but guidelines to
minimise skin loss are as follows:
n correct
variety choice
n control
of foliar diseases
n correct
timing of harvest
n correct
drying and storage procedure
n
avoiding
high temperatures and low humidities prior
to grading.
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Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
APPENDIX 1: TYPICAL APPLICATION RATES FOR NUTRIENTS (KG/HA)
Nutrient (kg/ha)
Soil Index
0
1
2
3
4
4+
Spring established
175
125
100
25
0
0
Overwintered*
50
0
0
0
0
0
200
150
100
50M
0
0
All soils
250
200
100 (2+)
0
0
0
Magnesium
150
100
0
0
0
0
Nitrogen - mineral soils
Phosphate
All soils
Potash
150 (2-)
Notes:
* Seedbed N is only required on mineral soils. Spring topdressing of up to 100kg/ha nitrogen may be required.
Nitrogen index is defined by: previous cropping, or residual mineral nitrogen sampling, which is the preferred option
Nitrogen index as defined by previous crop
Index 0
Index 1
Index 2
Any crop in field receiving large and
frequent dressings of FYM or slurry
Cereals, Sugar Beet, Maize
Beans or beans, potatoes, oilseed rape
Vegetables receiving less than 200kg/ha
Vegetables receiving more than 200kg/ha
Forage crops removed
Forage crops grazed
Lucerne
Leys (1-2 year), grazed or cut and grazed,
low nitrogen (1)
Leys (1-2 year), grazed or cut and grazed,
high nitrogen (2)
Long leys, grazed or cut and grazed,
high nitrogen (2)
Leys (1-2 year), cut only
Long leys, cut only
Permanent pasture, cut only,
grazed or cut and grazed
Permanent pasture, poor quality, matted
Long leys, grazed or cut and grazed, low
nitrogen (1)
Notes:
(1)
less than 250kg/ha nitrogen per year and low clover content.
(2)
more than 250kg/ha nitrogen per year or high clover content.
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
10
APPENDIX 2: GUIDELINES ON MINIMISING PESTICIDE RESIDUES
These guidelines have been produced after consultation between crop stakeholders and the Fresh Produce crop
author. They will be developed over the coming seasons as knowledge on minimising residues develops. Growers
should consult with their crop protection adviser to ensure other best practices are not compromised before considering
these guidelines. The table below lists the active ingredients that may give rise to crop residues and details potential
alternative strategies.
Active ingredient
maleic hydrazide
11
Target: pest,
weed, disease
Plant growth regulator
Current position
Residues found regularly
between the limit of
determination and MRL
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
Suggested guidelines
Growers should not apply maleic
hydrazide to garlic bulbs which are
destined for marketing prior to
1st December, as internal sprouting
is rarely significant prior to this
date. Use reduced product rates
for crops held in ambient storage
© Assured Food Standards 2015
NOTES
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
12
NOTES
13
Red Tractor Assurance for Farms – Crop-specific Module: Garlic
© Assured Food Standards 2015
Certification Bodies
Your routine point of contact with the Scheme is through your Certification Body.
Certification Bodies are licensed by Red Tractor to manage membership applications and to carry out assessment
and certification against the Standards. The table below shows which Certification Bodies apply to each enterprise.
Certification Body
NSF
Kiwa PAI
SAI Global
SFQC
Beef and
Lamb
Dairy
Combinable
Crops and
Sugar Beet
Fresh
Produce
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
NIFCC
(Northern Ireland)
4
QWFC (Wales)
4
Pigs
Poultry
4
4
4
4
4
4
4
NSF Certification
Kiwa PAI
Hanborough Business Park
Long Hanborough
Oxford OX29 8SJ
Tel: 01993 885739
Email: [email protected]
Web: www.nsf-foodeurope.com
The Inspire,
Hornbeam Square West, Harrogate,
North Yorkshire HG2 8PA
Tel: 01423 878878
Email: [email protected]
Web: www.kiwa.co.uk/pai
SAI Global Assurance
Services Ltd
PO Box 6236,
Milton Keynes MK1 9ES
Tel: 01908 249973
Email: [email protected]
Web: www.saiglobal.com/assurance
QWFC
SFQC Ltd
NIFCC [Northern Ireland]
QWFC [Wales]
Royal Highland Centre,
10th Avenue, Ingliston,
Edinburgh EH28 8NF
Tel: 0131 335 6605
Email: [email protected]
Web: www.sfqc.co.uk
Lissue House,
31 Ballinderry Rd, Lisburn,
Northern Ireland BT28 2SL
Tel: 028 9263 3017
Email: [email protected]
Web: www.nifcc.co.uk
PO Box 8, Gorseland,
North Road
Aberystwyth SY23 2WB
Tel: 01970 636688
Email: [email protected]
Web: www.wlbp.co.uk
T: 01932 589 800
E: [email protected]
www.redtractorassurance.org.uk
Fresh Produce
Standards